def test_parse_expression():
"""test parsing rio-tiler expression."""
assert sorted(parse_expression("b1*b11+b3,b1*b2+B4")) == [1, 2, 3, 4, 11]
assert sorted(parse_expression("b1*b11+b3,b1*b2+B4", cast=False)) == [
"1",
"11",
"2",
"3",
"4",
]
def tile(
self,
tile_x: int,
tile_y: int,
tile_z: int,
tilesize: int = 256,
indexes: Optional[Sequence] = None,
expression: Optional[str] = "",
**kwargs: Any,
) -> Tuple[numpy.ndarray, numpy.ndarray]:
"""Read a TMS map tile from a COG."""
kwargs = {**self._kwargs, **kwargs}
if isinstance(indexes, int):
indexes = (indexes, )
if expression:
indexes = parse_expression(expression)
tile = morecantile.Tile(x=tile_x, y=tile_y, z=tile_z)
if not self._tile_exists(tile):
raise TileOutsideBounds(
"Tile {}/{}/{} is outside image bounds".format(
tile_z, tile_x, tile_y))
tile_bounds = self.tms.xy_bounds(*tile)
tile, mask = reader.part(
self.dataset,
tile_bounds,
tilesize,
tilesize,
dst_crs=self.tms.crs,
indexes=indexes,
**kwargs,
)
if expression:
blocks = expression.lower().split(",")
bands = [f"b{bidx}" for bidx in indexes]
tile = apply_expression(blocks, bands, tile)
return tile, mask